I'm thinking of developing dedicated LiteBSD hardware board. My thoughts:- PIC32MZxxEFxx MCU. Is there any problem with it? Compared to EC series it seems to have fixed some nasty hardware bugs. I don't believe the EC will be ever fixed (just like dsPIC30F6012 was never really fixed, but reworked and released as new device), so there is no point in sticking with it for new designs. Hardware floating point unit will not hurt either.- some kind of networking. What to use? LAN8720 and wired ethernet? What about wifi? There are builds for Wifire board, does it utilize the wi-fi module? ESP8266 seems to be popular in hobby segment too. - USB/serial converter attached to USART. This is just handy and allows serial bootloaders to be used. - USB device port.- USB host? Can we utilize USB host in any way?- microSD card, appropriate power supply, reset/bootloader buttons, few LEDs- RTC. Can we utilize RTC?- lots of IO pinheaders- 10x5cm space, to fit low-cost chinese PCB suppliers.- I'd like to manufacture a few boards and distribute it to folks in this forum.

_________________Why not visit my shop? http://majenko.co.uk/catalogUniversal IDE: http://uecide.org"I was trying to find out if it was possible to only eat one Jaffa Cake. I had to abandon the experiment because I ran out of Jaffa Cakes".

IoT does not need MMU..ESP32 can work (except its wifi or bt function) as a realtime coprocessor (doing some useful work, under rtos), and the RetroBSD (or LiteBSD when mature) can work as a presentation or UI layer..

IoT may not need MMU, but LiteBSD does. Without that it will only ever be a peripheral to the PIC32MZ core processor.

_________________Why not visit my shop? http://majenko.co.uk/catalogUniversal IDE: http://uecide.org"I was trying to find out if it was possible to only eat one Jaffa Cake. I had to abandon the experiment because I ran out of Jaffa Cakes".

I agree with you. An OEM board using MZ...EF looks interesting. And I would be happy to help .

Most folks seem addicted to Arduino 'bus' and form factor. I think there are better ideas already out there!

MMU is clearly needed, but I have yet to see it work. I do have an MZ...EF board, but really want to read and store what is in its flash before I start to fiddle. MZ looks like a pretty well thought out product from what I see so far. So the MZ...EF is probably good to start out with?

As far as the 'try another micro' comments go, every time a new chip is announced the world nervously tries to figure out whether this is 'the' solution to their problems.... [ repeated over and over again ]

Basically the EF series core work on the same way like the EC series, then the behavior is the same for example on our boards with EF we have EC series bootloader. If you activate hard-float fpu unit then you can got more performance on float point operations, we have this activated on the LuaOS project developed by my friend Jaume, because Lua type is basic float..... and extended 64bit float works pretty fine....

Other brands are nice too, but try to make basic computer on one layer and few components, ....

Well- regarding the memory - it is not trivial or cheap to add much memory. It is easy to add SRAM, which is quite expensive (few bucks per MB). On the other hand, it is not easy to add SDRAM, which is cheap (few bucks per 128MB). On retrobsd I had up and running SDRAM bitbanged bus, though the bitbanged interface contains some magic sauce in MIPS assembly by madscifi I don't comprehend for 100%.- there is new, absolutely must-have and world changing micro every week- defintely no Arduino form factor. The only good thing about Arduino compatibility are cheap expansion boards (no way I'm gonna call it shield), but those are often designed for 5V and honestly - it is usually trivial hardware and I can't think of any that would be worth the work.

- what about the RTC, Ethernet via LAN8720, wifi or USB host? Any ideas about it?

I think the Retro community shall first decide/think where the pic32mz with LiteBSD shall be actually positioned, and who are the potential users, and what kind of problems it shall help to solve.Anything more than an Xtal and an sdcard socket added to the nacked pic32mz chip shifts the design into an area which is already occupied by _very_ cheap XYZ x more powerful gadgets with _huge_ amount of active users..Qs:1. how your design will be unique2. what kind of problems you can actually solve with it3. why your design can solve the problem better4. who will play with it and why...p.PS: or you may follow the "because we can" philosophy, some of us do like much

My ambitions are to create board useful for other community members (if there would be interest), not looking at money or time. There are Linux boards as cheap as single PIC32MZ, so nobody sane could expect some groundbreaking success here or solving any problems.On the other hand, it is fun to play with and anybody can solder it at home, using simple components (no BGA and similar stuff) and accessible PCBs (something like 10-20 USD per 10 pieces).

My only requirements would be the ability to add RAM for local compiling (even if it's 32/64MB that would get a significant amount of stuff built, and I could pay for/install the RAM module myself) and Ethernet (LAN8720 would be fine).

Nice board! With serial-to-USB chip as console port and LAN8720 it will be the best platform for LiteBSD development.

jaromir wrote:

- PIC32MZxxEFxx MCU. Is there any problem with it? Compared to EC series it seems to have fixed some nasty hardware bugs.

I don't observe any issues with MZ-EF chip. I have only one such board, though (chipKIT Wi-Fire).

jaromir wrote:

- some kind of networking. What to use? LAN8720 and wired ethernet? What about wifi? There are builds for Wifire board, does it utilize the wi-fi module? ESP8266 seems to be popular in hobby segment too.

I have tested four transceivers, namely LAN8720A, LAN8740A, IP101G and LAN9393. All these work fine. I would propose to install either LAN8720A or IP101G, as the latter promises less power consumption.

jaromir wrote:

- USB/serial converter attached to USART. This is just handy and allows serial bootloaders to be used.

This is a must have, as currently there is no USB bootloader available for MZ.

jaromir wrote:

- USB device port.- USB host? Can we utilize USB host in any way?

It is possible to port the whole USB stack from NetBSD or from OpenBSD. It's a huge amount of work though.

Serge, thanks for reply. So, it is getting shape - what is going to be on board:- PIC32MZxxEF- USB/serial converter hooked on USART.- SD card with option to power it up/down via single GPIO- LAN. For now I'm thinking of LAN8720A, because it is cheap and plentiful. IP101G may look interesting, but I'm having problems finding reliable supplier of this chip.- PCF8563 or similar I2C RTC, perhaps something like MCP79402. The latter one has unique EUI-64 MAC number on board, useful for networking.- pinheaders- small things like PSU, LEDs, buttons

What is omitted for now:- USB host.

What I'm unsure about yet:- Wi-fi. This would be cool and whatnot, but I'm not completely sure how much different is Wi-fi versus LAN from LiteBSD perspective. Could ESP8266 * be persuaded to serve as LiteBSD networking peripheral? What about the Wi-fi module on Wifire board?- Huge SDRAM.

Once I'll be clear about Wi-fi, I'll collect all parts footprints and do feasibility study.

- LAN. For now I'm thinking of LAN8720A, because it is cheap and plentiful. IP101G may look interesting, but I'm having problems finding reliable supplier of this chip.

I've seen a few offers of IP101G on AliExpress (1, 2, 3). Not sure though how reliable these guys are. LAN8720A is OK though.

jaromir wrote:

- PCF8563 or similar I2C RTC, perhaps something like MCP79402. The latter one has unique EUI-64 MAC number on board, useful for networking.

Actually we don't need an extra MAC, as every PIC32MZ comes with unique address preprogrammed in EMAC1SA0...EMAC1SA2 registers.

jaromir wrote:

What is omitted for now:- USB host.

It's OK for me. We can use other boards for USB development, like chipKIT Wi-Fire, Olimex HMZ144 and Whitecat.

jaromir wrote:

What I'm unsure about yet:- Wi-fi. This would be cool and whatnot, but I'm not completely sure how much different is Wi-fi versus LAN from LiteBSD perspective. Could ESP8266 * be persuaded to serve as LiteBSD networking peripheral? What about the Wi-fi module on Wifire board?

This would be a killer feature! I mean, ESP8266 in raw mode. AFAIK, people managed to develop a Linux driver for it (https://github.com/al177/esp8089) - so it's definitely possible. But may be it makes sense to create another board with ESP and without Ethernet.

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